With the Labor Day holiday weekend, health officials are urging people to stay away from parts of the river.

"Stanton Park in Canyonville to one-half mile below the Myrtle Creek Bridge," Jerald Meyer with Douglas County Health Department, "and then this coming week DEQ will be sampling that entire stretch of the river to see how bad those algae concentrations are."

The Department of Health tested the water after a dog died while visiting lawson bar outside of Canyonville.

Signs are posted at Lawson Bar warning of the health advisory, and large algae blooms can be seen sitting in the water.

The toxic algae is especially harmful to pets and children, and it only took two hours to kill a dog that weighed 60 pounds.

"The possibility of children being in the river at that time and because of the huge difference in toxic levels from last year to this year, we want to make sure we get the message out to the public," Meyer said.

Toxic blue-green algae can't be filtered or boiled out of water, so it shouldn't be used for cooking.

Health advisories have been lifted at Diamond, Lemolo, and Fish lakes.